Defrosting arrangement



Jan. s, 194e'. A

c. Mi ASHLEY y DEFROSTING ARRANGEMFIT 2 Sheets-Sheet'l Filed May 2o,194:5

FIG. I

FIG. 2

INVENTOR ATTORNEY.

Jan. 8, 1946. c. M. ASHLEY l 2,392,528

l I DEFROSTING ARRANGEMENT Filed May 20, 1943 2 Sheets-Sheet 2 FIG.3

INVENTOR. BY i ATTQRNEY.

. drainage by gravity from the water coils.

Patented Jan.8, 194

nEmo'sTING ARRANGEMENT Carlyle M. Ashley, Syracuse, N. Y., assignor toCarrier Corporation, Syracuse, N. Y., a corporation of DelawareApplication May 20, 1943, Serial No. 487,746

8 Claims..

This inventionvrelates to defrosting by the use of water and moreparticularly to yrefrigeration and other systems wherein it is desiredto remove accumulations of lice and frost from a series of coils. j

A feature of the invention resides in the provision of a series ofchannels in a top or cover plate of an evaporator casing or the like. AWater coil positioned within each channel directs a ilow of water fordefrosting against the body of the channel. The water then flowsy towardand down the legs of the channel, dropping upon the coils to bedefrosted, which are positioned below and in vertical alignment with thelegs.

A further feature resides in providing for Since the coils have theirdischarge openings at the top, drainage 4by gravity will leave a spacein the coils at the top, eventhough gravity drainage is incomplete.Consequently, when the ilow of water for defrosting is resumed,sufiicient water will be circulated in such space to assure resumptionof defrosting operations, and to clean out such ice as may have formedbecause not all of the water had been drained at the conclusion of theprevious defrosting operation',

These and other features and advantages will be more apparent from thefollowing description of one form of the invention to be read inconnection with accompanying drawings in which: l

Fig. 1 is a diagrammatic View, in section, showing a series of coilsadapted to be defrosted by a water defrosting arrangement in accordancewith applicants invention;

Fig. 2 is a detailed view of a channel-member with a Water coilpositioned therein; and

Fig.A 3 shows, diagrammatically, a piping armay be done by cutting temserving coils 5,.,assuming a direct expansion system is used, or Wherebrine is circulated, the circulation may be stopped. Such shut-down isundesirable, sincethe temperature in the area served by the coils willundesirably rise. Therefore, it has been the aim of those skilled in theart to provide a system for defrosting speedily. Such attempts as havebeen made for defrosting by use of water have provided expensivevalveand vent arrangements, as well as complications in operation. Applicantssimple arrangement avoids such devices and eliminates substantially theuse of methods of operation which are subject to failure.

Since the use of afan, refrigerant feed arrangement for coils, anddetails of the casing 4, form I vertical rows numbered 6, l, 8, 9, i0,and lI are shown. These may be in casings, or otherwise positionedWithin '4.

rangement adapted to serve the channels used for with many such unitsfor circulating air over the "cold coils. The temperature of coils 5 isoften below the freezing point, with the' result that ice or frost willaccumulate uponthe coils, as is well known in the art.

Since the eiiiciency of the system in which such units may be employedis impaired when the accumulations of frost become excessive, it isnecessary to remove the frost periodically. This Channels I2 aresuitably aiilxed to cover plate I3 arranged to fit over casing. d, inwatertight' manner. A Water defrosting coil or pipe @Il is positionedwithin each channel l2. At the top of each pipe i is provided a seriesofvvater discharge openings I5. As shown in Fig. v2, the openings may bein the form of smallV holes, or shaped as desired, through which waterfrom pipes I4 is discharged upwardly against the inner surface of thetop or channel portion of i2, spaced preferably not more than an inchabovethe pipes. Each channel has a center channel portion IS and twolegs il, as shown in Fig. 2. The water discharged from pipes i4 upwardlyagainst center portion I6 mushrooms in a plurality of directions,

spreading longitudinally as well as transversely, and impinging againstboth legs Il, to form continuous` vertical sheets dropping from thelegs.

hecoils to be defrosted, 5are positioned in line with legs Il. Asumcient ilow of Water is provided over 'the frosted surfaces of coils 5so that the 1 surfaces will be raised in temperature and the frostrapidly melted away.

As shown in Fig-3 pipes I4 may be provided inI out the refrigerationsysv vdead ended so that a maximum pressure of discharge'throughorifices I5 will result upon opening valve I9. Pipe coil I4 may be amxedto the inside of the cover plate I3 as by brackets 22, and spacedtherefrom so that the pipes may depend as illustrated, below the channelmembers Pipes I4 have one or more drainage openings 23 at the bottom, sothat when valve I9 is closed and the supply of water shut off, drainageof such water as remains in the pipes will take place,4 at least inappreciable part, through drainage openings 2'3.

In Fig. 2.a dash dot line is shown within pipe I4. This is intended toillustrate a condition where subsequent to a frosting operation, pipesI4 have drained only partially. The result is that residue of water inthe bottom of pipes i4 is shown frozen, asT would take place duringrefrigeration periods between the times when defrosting takes place.However, when defrosting is desired, and valve I 9 opened, the surge ofwater in the open space above the ice, within pipes I4, will be sufcientto carry on the defrosting operation. The water will be dischargedthrough openings I upwardly and` then flow down -the legs I'I, drop-`ping upon the accumulations on coils 5. Since the water is much higherin temperature than the ice in pipes I4, it will soon cause the ice tobe melted away, thus freeing the whole interior area of the pipes forflow of water. The drainage openings 23 will also be cleared so that atthe conclusion ofthe defrosting operation they will be free to dischargewater by gravity from the.- pipes, as aforesaid.

Since various changes may be made Without departing from the scope ofthe invention, it is intended that all matter set forth in thedescription, or shown inthe drawings be regarded as illustrative onlyand not in a limiting sense.

I claim:

1. A method of defrostingcoils by the use of water and eiecting'drainageof water subsequent to defrosting consisting in supplying water up'frost will be removed from the surfaces, draining Y upward discharge,said water being drained by gravity.

2. In combination a casing, aA plurality of refrigerated coilspositioned within said casing',

a top member in the casing, a plurality of channels integral with thetop member, coils within the channels, means for discharging water fromsaid last mentioned coils upwardly against the channels, said channelshaving legs positioned above the coils in the casing in such manner thatwater discharged upwardly in the channels will flow from the legsdownwardly upon the coils in the casing, and means for draining thecoils in kthe channels. p

3. In combination, a casing, coils to be defrostedf positioned withinthe casing, a plurality of in# verted channels, said .channels beingpositionedv above said coils with the-legs of said channels chargedupwardly from the coils into the channels flowing from the channelsdownwardly upon the coils in the casing to be defrosted.

4. In a combination of apparatus of the character described a casing, atop cover sheet for the casing, a plurality of channels integral withsaid sheet, a series of defrosting coils positioned within saidchannels, orifices `in the upper sides of said coils facing saidchannels, an orifice in the lower side of said coils vfor enablingliquid in the coils to drain by gravity, each of said channels 'having aplurality of legs pointing-downwardly, a plurality of coils adapted toberefrigerated positioned in said casing below and in vertical alignmentwith said legs, and means for supplying liquid to said defrosting coils.v

5. A defrosting system of the character -de scribed for removing frostfrom a series of refrigerated coils, comprising a'series of defrostingcoils, means for supplying water to the defrosting coils, a plurality ofchannel members positioned above the defrosting coils, said membershaving a body portion and two legs, means for dischargf ing water fromthe defrosting coils upwardly against the body portion, said water owingdownwardly from the legs,l said refrigerated coils being positioned withrespect to said legs so that *water flowing from the legs will fall uponand wash away accumulationsy of frost from the re` frigerated coils. y

6. A method of defrosting 'refrigerated surfaces by the use of water andeifecting drainageA of Y water subsequent to defrosting, consisting insupplying water to a point of discharge, discharging said water at saidpoint upwardly against a target, repelling water from the target uponthe refrigerated surfaces whereby accumulations of said water and meltedfrost by gravity from the area in which the refrigerated surfaces arelocated, discontinuing the supply of water to said point, and drainingby gravity water remaining at said point of discharge after defrostinghas been completed. v

A 7. A method of supplying water for defrosting refrigerated surfacesand for draining water to prevent freezing 'at points of discharge ofsuch water, consisting in supplying water to a tube having orifices atthe top thereof, discharging water from the orifices against targets,repelling the Water from the targets upon refrigerated surfaces toremove fro'st therefrom, draining by gravitythe water and melted frostleaving the refrigerated surfaces, discontinuing the supply of the watertothe t e, and draining the tube by gravity at least at one pointthereof so that the water le'vel in the tube will lrecede from theorifices andleave a space between the orices and the level to which theWater in the tube recedes.

8. A method of defrosting refrigerated surfaces by theuse of water anddraining such water without the use of a positive vent .consisting insupplyin-gswater to a tubeA having a series of orifices above the centerline of the tube, discharging water from the tube through 'saidoricesagainst targets, repelling water from said targets upon a vseries offrosted coils, draining by gravity water and melted frost leaving thecoils, discontinuing the supply of water'to the tube and drainingthrough orifices in the bottom' of the tube such water as'will escape bygravity whereby the waterv in the tube will recede to avlevel below theoriiices. y

CARLYLE M. ASHLEY.

